Last week I had the opportunity to travel down to London and go to the Natural History Museum night safari, on the topic of evolution.We were allowed to go into the building at 6.30pm and at 7 the mini lectures started about 3 different elements of evolution.
The first lecture was on Island evolution. This is the idea that, on Islands, species often undergo dwarfism or gigantism. There are many cases of this but the one that we got to look at is elephant dwarfism. I never knew that elephants had even been present on islands, especially not Cyprus, Malta and Crete! The decrease in size may have been due to resources and that smaller individuals wouldn't have required as much food or other resources. The recent DNA analysis of the species
Elephas creticus has uncovered that the fossils found were actually not an elephant but a mammoth! These small elephants and the small mammoth are between 1.5-2.3m in comparison to the ancestors which is tiny, some were even as small as waist height!! There were also hippos on islands that had undergone dwarfism and were estimated to measure between 76-121cm!!
The first elephant fossil found was by a women called Dorethea Bate who was just 19 when she gained a job as the first female to work at the National History Museum in 1897 after she visited the museum and demanded a job. The bird curator found her so interesting that he offered her a job. Sometimes being witty really does have advantages!
The second mini lecture was by Roberto Miguez who is the curator of mammals at the Natural History Museum. He gave a talk on both evolution of the tenrecs family and how diverse the family are along with the idea of convergent evolution. This is the idea of independent evolution of similar features in species of different lineage. The tenrecs family are found in Madagascar and parts of Africa's mainland. Many of the species appear to look like shrews and hedgehogs but amazingly they share common ancestors with elephants even though their closest living relatives are the golden mole and the elephant shrew.
The third talk was on rapid evolution with the example Sticklebacks. He talked about how the species had evolved two forms depending on where they live. You could sometimes get both variations within the same place but the variation arose due to accidental mutations which had an advantage due to different areas having different predators. The spiny fish have the advantage when fish try and eat them, as they can get caught in the predators throat and so must be coughed up. Spines are a disadvantage in areas where they are caught by birds as it gives the birds something to hold onto so it is advantageous not to have them. The trait can save the fishes life so the gene leads to survival of the fittest and rapid evolution takes place.
After all 3 talks we got to wander around the museum at night included the
Britain: One million years of the human story exhibition which was really interesting with displays of real weapons which would have been used hundreds of thousands of years ago and you got to see how tall Neanderthals and humans really were all those years ago.
The experience cost £28 which seems quite a lot as you normally would get in for free but the Britain exhibition is £9 and the fact you get the opportunity to listen and speak to 3 respected scientists from the Natural History Museum along with wandering the museum with hardly any one present is a truly magical experience and I would definitely go again!!!
http://en.wikipedia.org/wiki/Cyprus_dwarf_hippopotamus
http://en.wikipedia.org/wiki/Dwarf_elephant
http://www.nhm.ac.uk/nature-online/science-of-natural-history/biographies/dorothea-bate/
No comments:
Post a Comment